The overall goal of this R25 training program is to offer a set of instructional and directed research opportunities to exceptional candidates that promote their careers as independent researchers in the field of cancer prevention and control. This application is a competitive continuation of the Prevention Research Educational Postdoctoral (PREP) training grant that offers a flexible 2-3 year training program. The program targets individuals for training who have received a doctorate in the social and behavioral sciences, public health, nursing and medicine. The training program consists of the following: 1) A brief, intensive core curriculum of didactic seminars designed to be completed within the first two months of the fellowship by all trainees;2) An individualized longitudinal curriculum offered through relevant academic departments and through the School of Medicine;3) Exposure to clinical oncology and basic cancer biology through didactic training and clinical rotations. This provides fellows with adequate exposure to and knowledge of the clinical settings in which cancer care and preventive services are delivered to patients;4) Development of tailored cancer prevention and control research experiences designed to expose fellows to a variety of research paradigms and disciplines;5) A mentored cancer prevention and control research project designed by the fellow in collaboration with his/her mentors. As conceptualized, the training opportunities and infrastructure support are transdisciplinary and focus exclusively on cancer prevention and control research. Upon entry into the program, the fellow is assigned a mentor who helps the fellow orient him/herself to the Cancer Center and University environments, evaluates the fellow's research and clinical experience, and helps the fellow choose a permanent primary mentor. During the first two months, fellows attend and complete the core curriculum and, with their initial mentor's help, select a primary mentor and the package of courses, seminars, clinical and brief research rotations that will prepare the fellow to conduct research in cancer prevention and control. Most fellows begin designing their research protocol in month 6 of the fellowship and assemble a multidisciplinary mentoring committee to help direct their research and career development throughout their training period. Solving crucial issues in the prevention of cancer and the optimization of treatment and survivorship is hampered by a paucity of researchers working in this field. The PREP addresses this problem by training the next generation of cancer prevention and control researchers.